Spells Through the Ages – Lightning Bolt

Had any summer thunderstorms lately? (We did last night.) Today, let's take a look at the effects of the D&D lightning bolt. Recall that lightning bolt has its true origin in the Chainmail mechanics for cannon-fire (with their bouncing-cannonballs line-of-effect), and, along with fireballs, was one of the two primary wizard powers called "Missiles" in that ruleset.

Chainmail Fantasy

In Chainmail Fantasy, lightning bolts were described in tandem with fireballs in the section detailing the wizard's "Missile" powers. See here.

Original D&D

Lightning Bolt: Utterance of this spell generates a lightning bolt 6" long and up to 3/4" wide. If the space is not long enough to allow its full extension, the missile will double back to attain 6", possibly striking its creator. It is otherwise similar to a Fire Ball, but as stated in CHAINMAIL the head of the missile may never extend beyond the 24" range. [OD&D Vol-1, p. 25]
As usual, OD&D was built on a foundation that assumed use of Chainmail for all the basics of turn sequence, combat, morale, ranged weapons fire, fantasy unit abilities, etc., etc. The lightning bolt spell is one of many places that explicitly highlight this linkage. Note that while the area in Chainmail was simply "3/4" wide", here it is given variation of "up to 3/4" wide" (I'm not sure what the advantage might be to that). Vol-3 has additional commentary on the "rebound" rule, which was introduced for both fireball and lightning bolt in exchange for not blowing up stonework equal to their full volume. I find that rule pretty suspect: see here (under OD&D).

Holmes D&D

Lightning bolts are not detailed in Holmes D&D. No spellcaster powers of 3rd level or above are so given in the book. Although the wand of fireballs was included among the list of magic items (again: here under Holmes D&D), the wand of lightning bolts was not. Perhaps this signals the greater iconic standing of the fireball over its sister spell (and also its higher power/area-of-effect).

Advanced D&D (1st Edition)

Lightning Bolt (Evocation)

Level: 3
Range: 4" + 1"/level
Duration: Instantaneous
Area of Effect: Special
Components: V, S, M
Casting Time: 3 segments
Saving Throw: ½

Explanation/Description: Upon casting this spell, the magic user releases a powerful stroke of electrical energy which causes damage equal to 1 six-sided die (d6) for each level of experience of the spell caster to creatures within its area of effect, or 50% of such damage to such creatures which successfully save versus the attack form. The range of the bolt is the location of the commencement of the stroke, i.e. if shot to 6", the bolt would extend from this point to n inches further distance. The lightning bolt will set fire to combustibles, sunder wooden doors, splinter up to 1' thickness of stone, and melt metals with a low melting point (lead, gold, copper, silver, bronze). Saving throws must be made for objects which withstand the full force of a stroke (cf. fireball). The area of the lightning bolt's effect is determined by the spell caster, just as its distance is. The stroke can be either a forking bolt 1" wide and 4" long, or a single bolt ½" wide and 8" long. If a 12th level magic-user cast the spell at its maximum range, 16" in this case, the stroke would begin at 16" and flash outward from there, as a forked bolt ending at 20" or a single one ending at 24". If the full length of the stroke is not possible due to the interposition of a non-conducting barrier (such as a stone wall), the lightning bolt will double and rebound towards its caster, its length being the normal total from beginning to end of stroke, damage caused to interposing barriers notwithstanding. Example: An 8" stroke is begun at a range of 4", but the possible space in the desired direction is only 3½"; so the bolt begins at the 3½" maximum, and it rebounds 8" in the direction of its creator. The material components of the spell are a bit of fur and an amber, crystal or glass rod. [1E PHB, p. 74]
Again, an expansion similar to that of fireball. In fact, the connection of the two "missile" spells is still explicit, as the new information on heat and destructiveness to inanimate objects refers back to the other spell for details ("cf. fireball").

In OD&D we saw an allowed area of "up to 3/4" wide"; now the option is restricted to one of two types, either 1" or ½" wide. (The width has modified a bit like that each edition.) The length is no longer simply 6" (classic multiple-of-3 as per the roots of the system), but either 2" shorter or longer (depending on the width chosen).

Whereas in prior editions, the range for both fireball and lightning bolt was an identical 24", here the lightning bolt appears to be given a disadvantageous range (fireball 10"+1"/level versus lightning bolt 4"+1"/level). However, that's counterbalanced by a change in direction to how the bolt head is placed: previously it said "body extends 6" behind it" [CM/OD&D], but now we are told, "the bolt would extend from this point to n inches further distance". So in some sense we've gained back the 6" difference; wizards can't be hit by placing their lightning bolts too close, and the spells have an equal total range (at least on average) like they used to.

Finally, a little bit of extra detail in the errata-like section of the DMG:
Lightning Bolt: Note that physical damage is not exceptional, so that if a solid wall is struck, the bolt effectively rebounds its full remaining distance. If it strikes a barrier which is shattered/broken through by the force of the stroke, then the bolt continues beyond. [1E DMG, p. 45]

Advanced D&D (2nd Edition)

Lightning Bolt

Range: 40 yds. + 10 yds./level
Duration: Instantaneous
Area of Effect: Special
Components: V, S, M
Casting Time: 3
Saving Throw: ½

Upon casting this spell, the wizard releases a powerful stroke of electrical energy that inflicts 1d6 points of damage per level of the spellcaster (maximum damage per level of 10d6) to each creature within its area of effect. A successful saving throw vs. spell reduces this damage to half (round fractions down). The bolt begins at a range and height decided by the caster and streaks outward in a direct line from the casting wizard (for example, if a 40-foot bolt was started at 180 feet from the wizard, the far end of the bolt would reach 220 feet (180 + 40). The lightning bolt may set fire to combustibles, sunder wooden doors, splinter up to a half-foot thickness of stone, and melt metals with a low melting point (lead, gold, copper, silver, bronze). Saving throws must be rolled for objects that withstand the full force of a stroke (see the fireball spell). If the damage caused to an interposing barrier shatters or breaks through it (i.e., the saving throw fails), the bolt continues. A bolt can breach 1 inch of wood or half an inch of stone per caster level, up to a maximum of 1 foot of wood or half a foot of stone.

The lightning bolt's area of effect is chosen by the spellcaster: either a forked bolt 10 feet wide and 40 feet long or a single bolt 5 feet wide and 80 feet long. If a bolt cannot reach its full length, because of an unyielding barrier (such as a stone wall), the lightning bolt rebounds from the barrier toward its caster, ending only when it reaches its full length.

For example: An 80-foot-long stroke is begun at a range of 40 feet, but it hits a stone wall at 50 feet. The bolt travels 10 feet, hits the wall, and rebounds for 70 feet back toward its creator (who is only 50 feet from the wall, and so is caught in his own lightning bolt!).

The DM might allow reflecting bolts. When this type of lightning bolt strikes a solid surface, the bolt reflects from the surface at an angle equal to the angle of incidence (like light off a mirror). A creature crossed more than once by the bolt must roll a saving throw for every time it is crossed, but it still suffers either full damage (if one saving throw is missed) or half damage (if all saving throws are made).

The material components of the spell are a bit of fur and an amber, crystal, or glass rod. [2E PHB, Appendix 3]
As expected, that's mostly the same as in 1E. It even still has the "see the fireball spell" linkage in regards to inanimate object saves. Like fireball in 2E, damage has been capped at 10d6. Range has been converted from sliding-scale "inches" to yards (which is a greatly advantageous shift underground; in fact, it's now actually longer than a fireball by 30 yards due to 2E's unique stubbing of that latter spell's range formula). The 1E DMG note on traveling through a shattered barrier is absorbed here (1st paragraph, 2nd-to-last sentence). We also get some explicit thumbnail rules on how thick a barrier it's likely to break for the first time (in the following sentence).

The one totally brand new thing is DM's option to "allow reflecting bolts" (the 4th paragraph), with angle of reflection equal to angle of incidence, as light would actually bounce off a mirrored surface. This would be a change from prior rules where any rebound is always back at the caster (or perhaps just always presuming a perpendicular wall to the caster). As before, I propose the alternate solution of possibly having lightning bolts simply ground into the earth when they hit a solid barrier.

Rules Cyclopedia

Lightning Bolt
Range: 180'
Duration: Instantaneous
Effect: Bolt 60' long, 5' wide

This spell creates a bolt of lightning, starting up to 180' away from the caster and extending 60' in a straight line further away. All creatures within the area of effect take 1d6 points of damage per level of the spellcaster. (Thus a 6th level elf would cast a lightning bolt doing 6d6 points of damage.)

Each victim may make a saving throw vs. spells; if successful, he takes only half damage.

If the lightning bolt strikes a solid surface (such as a wall), it will bounce back toward the caster until the total length of the bolt is 60'. [RC, p. 49]
A simpler version than AD&D, which more-or-less maintains the same content as the OD&D language. Area is fixed: always 60' long and 5' wide. As in 1E, it looks like the spell has been shortened (fireball 240', lightning bolt 180'), but when we include the switch-around that the bolt extends forward instead of back, we see that we can still hit something 180+60 = 240 feet away, just like a fireball. The rebound rule is the same as it always was (no 2E style light-like reflection option mentioned). Contextually we recall that BXCMI/RC cap all damage spells at 20d6 (a lot more potent than the 10d6 fireball/lightning cap we got in 2E). And this is the first example we've seen that didn't include a specific link or reference back to fireball.

d20 System D&D (3rd Edition)

Lightning Bolt

Evocation [Electricity]
Level: Sor/Wiz 3
Components: V, S, M
Casting Time: 1 action
Range: Medium (100 ft. + 10 ft./level) or 50 ft. + 5 ft./level
Area: 5 ft. wide to medium range (100 ft. + 10 ft./level); or 10 ft. wide to 50 ft. + 5 ft./level
Duration: Instantaneous
Saving Throw: Reflex half
Spell Resistance: Yes

The character releases a powerful stroke of electrical energy that deals 1d6 points of damage per caster level (maximum 10d6) to each creature within its area. The bolt begins at the character's fingertips.

The lightning bolt sets fire to combustibles and damages objects in its path. It can melt metals with a low melting point, such as lead, gold, copper, silver, or bronze. If the damage caused to an interposing barrier shatters or breaks through it, the bolt may continue beyond the barrier if the spell’s range permits; otherwise, it stops at the barrier just as any other spell effect does. [3E SRD]
This spell description seems to be cut down quite a bit from the prior AD&D line. There's no link to fireball; there are no guidelines for how thick a barrier might be broken; and there are neither any rebound or reflection rules, making it safer for the caster (very much in character for the 3E system). The pass-through-broken-barrier language from the 1E DMG is still included.

The other idea that has been terminated is the use of a separate "bolt" area to be laid down on the tabletop at a distance from the caster (inspired, again, by the bouncing cannonballs shot from Chainmail's cannons). Now the spell simply affects everything from the caster's "fingertips" to the maximum range of the spell. Apparently in compensation for this, the range has been radically reduced in comparison to fireball (400+40 ft/level in 3E), being only one-quarter or one-eighth the total range of that spell (depending on width chosen).

Fireball has always had a great advantage over lightning bolt in terms of overall area-of-effect (in the earliest rules, 12.6 square inches for the former, versus 4.5 for the latter). I think this is even more pronounced in the open field (facing enemies more likely to be in a long line than a deep column; making it hard for the rail-thin lightning bolt to cross multiple figures). Perhaps lightning bolt gains an increase in usefulness in the dungeon, with enemies pinned down in a long corridor in front of the caster? But I think in 3E the massive gimping of the range, along with lack of flexibility in affecting figures directly next to the caster, make it a far less preferable spell in many or most circumstances (even if overall area is now comparable at around, say, 15th level).

(Photo by Pete Hunt under CC2.)


  1. I always ruled the "same angle as wall is hit" way. I like the tactical possibilities als well as the possible mishaps.

    My fireballs still fill out the same space as they would have had as a sphere, too... goodbye, kobold warrens.

  2. I'd like a post on dragon fire as well.

    Question: even if dungeon exploration is at 1"=10 feet, why wouldn't combat be tied to the base size of figures? If 3 mem can stand down a 10 foot hall (1" in exploration maping scale) why wouldn't a figure on a 3/4" base be the actual size of the lightning bolt? I.E. The width of 1 figure? Certainly lightning bolts outdoors isnt 7 yards wide is it?

    This is why I feel range may comport with indoor/outdoor scale, but spells and man to man should be just that, man to man.

  3. I do the billiard-ball lightning bolt bounce. I also say no target can be hurt more than twice by one lightning bolt, which prevents a lightning-immune caster from standing beside a monster in a 10' corridor and firing a lightning bolt perpendicular, hitting him 16 times (save for half!).

    Also, for Fireball, I do 20' radius, doubled indoors, quadrupled in tight spaces. Indoors is normal 10' corridors and rooms. Tight is 5' sewer-like corridors. This accounts both for ceiling height and lateral space, so a large room with a high ceiling might just count as outdoors. Just draw it over walls and such, and areas that are "cut off" such as behind a door or something are unaffected.

    We just had two consecutive Fireballs almost totally waste the PC group. The surviving PCs scrambled around heailng and Raising Dead while the lone surviving Displacer Beast streaked out of there yowling.

    Gotta watch that backdraft.

  4. Oh also, I tell players to choose where they target a spell and I draw the area of effect. If the line is really tight, say hurling a Fireball along a line that cuts diagonally and just misses several corners, I have him roll a 50-50 for success. But I let him know ahead of time that it will be really close and the chance he could hit the wall.

  5. UWS Guy: Again I agree that's how it should be, but Gygax didn't think it through in the original rules (ideally 1"=5 ft., i.e., about figure scale). Like in Swords & Spells lightning bolts actually were 7 yards wide (S&S, p. 12). Later in AD&D you finally get the rule that areas should be read as feet indoors (PHB p. 39: all-caps section).

  6. 1d30: Interesting stuff. One thing I did was get a 2" radius brass ring that players could just drop on the map (around minis) as desired. This saved time (no drawing needed), but I got cranky when some took a lot of time deciding on an optimally perfect "drop". So that was a bit of a mixed bag.

  7. ... and I'm no longer using minis at all lately for dungeon action, so it's not an option anymore, really.